2. More on Formula Hybrid’s basic parameters

University of Madison Wisconsin gets ready to run the track at the 3rd annual Formula Hybrid International Competition.

In this week’s second Formula Hybrid blog I continue, with Doug Fraser’s help, to discuss the primary rules and theories that define the annual early May contest at the New Hampshire Motor Speedway. Doug starts this week by describing his essential concept of the Formula Hybrid rules.

“Of course, there are many different hybrid configurations,” Fraser notes. “The Formula Hybrid  rules require that the vehicle has an internal combustion engine and an electric motor system as opposed to hydraulic accumulators, flywheels and fuel cells. The only devices that are approved for electric accumulators are batteries or capacitors and they have very different characteristics that can be used to advantage in different ways.”

A significant change from the SAE rules was reducing Formula Hybrid’s maximum engine size from the SAE’s 600cc to 250cc. “In a hybrid the 250cc engine is more than enough to get the car around very smartly,” Fraser says. “None of the teams have ever objected to that. It’s worked out just fine.”

There’s no minimum or maximum weight for Formula Hybrid. The cars must have four wheels and a minimum wheelbase of sixty inches. “We have deliberately set up a minimum of rules because we want the students to be as creative as they can be,” Fraser relates.

“We do have rain tire policies but there are no tire rules. There are grooving requirements for rain tires. We don’t allow hand-cutting of grooves and they can’t change wheel types after the judging has been done or use tire warmers or traction enhancers. But other than that, it’s wide-open.”

Formula SAE requires a new frame every year but Formula Hybrid allows older chassis to run as long as they are safe. “Formula SAE has been really successful and their fields filled up to the point where they had to do something to throttle it down a little bit,” Fraser says. “They used to allow second-year cars with a penalty but then some years later they said each car has to be built from scratch with a brand new frame.

A team works in the paddocks at the 4th annual Formula Hybrid International Competition.

“But we said we would permit multiple year cars. In fact, we encouraged teams to resurrect old Formula SAE cars, strip the engine and drivetrain out and hybridize it. Unless there was a serious safety issue involved — our rules lag Formula SAE by three years. If your chassis complied with Formula SAE rules three years ago you would probably be able to get it into Formula Hybrid.”

The chassis rules are largely unchanged from Formula SAE. The same chassis strength and impact attenuators are required plus SAE-spec driver protection for driver’s suit, helmet and safety gear. But the electrical rules are very different. “The voltages aboard a Formula Hybrid car are lethal,” Fraser emphasizes. “Particularly when undergraduates are in the garages pulling all-nighters trying to get their cars fixed during the event. So we have a lot of rules regarding systems isolation.”

A Formula Hybrid car must have three kill switches or ‘Big Red Buttons’. Two of them are located on each side of the roll bar so safety or emergency crews can hit them easily. The third button is located within easy reach of the driver. “Hitting that button drops out the entire electrical system and shuts everything off,” Fraser says. “All the relays are shut off so that no voltage will appear outside the accumulator housings.”

There are also strict rules to isolate the high voltage from the low voltage system that runs ancillary things like brake lights and the dash panel. “The twelve-volt system has to be well isolated from the high voltage system,” Doug stresses. “We have a rule that says there will be no high voltage wiring anywhere inside the driver’s compartment. All the controls have to be isolated if you’re using fiber optics or transformer couplings so that there’s no electrical connection at all between the low voltage system, the high voltage system and the chassis of the car.”

Another important electrical component is the ground fault interrupter, supplied free to the teams by the Bender Corporation. “It’s a small circuit board about the size of a Coke can,” Fraser explained. “It sits in the car and watches the high voltage system in relation to the car’s frame and twelve volt wiring. If there’s any leakage at all between those two systems it shuts everything down. It’s a very important component.”

Additional precautions are taken for running in the rain which requires a further technical inspection. “There’s an underwriters laboratory design nozzle that is specifically designed for checking the integrity of the electronic systems when they’re wet,” Doug says. “The tech inspectors reserve the right to spray the student cars with water. If the ground fault interrupter trips they won’t be approved to run in the rain.”

A Formula Hybrid’s accumulator is limited to 4,449 watt hours, just under 4.5 kilowatt hours, and can’t cost more than $6,000. “We can’t have these kids buying ultra-lightweight aerospace stuff,” Fraser said. “So we set a standardized cost for the accumulator based on what the average customer walking into the store can buy the stuff for. It can’t be some special prize that the student team negotiated with the manufacturer.”

The accumulator is closely monitored both electronically and visually. “It can be spectacular when these things overheat and fail,” Doug remarks. “So we talk a lot in the rules about isolation of the accumulator from the drivers or students working on the vehicle. Part of the accumulator housing has to be transparent so you can see in there and see smoke or something. We’re also very specific about marking and locating high voltage stickers.”

Dartmouth College's hybrid team initiated and now sponsors the annual Formula Hybrid™ competition. Fourteen teams from around the world gathered to compete in the 2008 event.

Technical inspection of the cars is kept to a rigorously high standard. “The mechanical tech inspection is about the same as Formula SAE,” Fraser observed. “The students have about the same type of difficulty in getting through it. Maybe twenty percent of the teams struggle to get through mechanical tech inspection. But electrical inspection is a lot harder. We’ve posted a number of items that give teams examples of good and bad designs.”

Fraser could not be more pleased with the quality of Formula Hybrid’s wide selection of technical inspectors, rules committee and judges. “We beat the bushes really hard to find the best people,” he said. “I think we’re pretty fortunate because we’re getting pretty close to a critical mass where we can start being picky about who comes on board which is really nice.

“We have a very strong group of chief technical inspectors. We recruit a lot of SCCA people. I tend to call on my connections from the old days. The electrical inspectors come out of a different pool. We’ve been pretty fortunate in having people from battery companies come on board and we have two people from Thayer, Jenna Pollock and Charles Sullivan, both PhDs in high power electronics.”

Fraser’s key right hand person in bringing Formula Hybrid to life is Wynne Washburn. “I do most of the technical stuff,” Doug says, “and Wynne does pretty much everything else — all the administration, promotion and marketing.”

Washburn has been at Thayer since 2006 and is working on her thesis in globalization and sustainability for a Master of Liberal Studies. “It’s a similar thing to Formula Hybrid,” Wynne remarked. She hopes to earn her masters degree in the spring.

“Doug roped me into Formula Hybrid,” Wynne grinned. “It works really well because there are a lot of things I know how to do that Doug doesn’t and vice-versa. So we work together as a good team. We literally started this thing together. We’ve been working on it together since day one.”

Washburn is responsible for generating the funding for Formula Hybrid. “It’s a lot of work,” she said. “But we’re starting to see more and more companies and corporations coming to us who are curious about what the competition is all about and how they can get involved. At the beginning, through a friend of a friend of a friend who worked at Toyota, I called them and months later Toyota became our first sponsor besides Thayer. Then we started to be approached by interested companies. So we’re gathering interest and strength.”

Wynne says Formula Hybrid’s impressive panel of judges is a key element in attracting sponsors. “Our judges are from all over different industries and when they come and see what we’re doing they get excited about it. They want to be more involved and as a result their companies become more involved. They have responded really well. It’s a process that’s gaining more and more momentum.”

Fraser has handed off his role as Dartmouth’s team advisor to John Collier. “When we started the Formula Hybrid project I stayed involved with the team for a while,” Doug says. “But then we handed it off to another faculty member, John Collier. It had become a conflict of interest for me to be one of those running the competition and at the same time help one of the teams win. So John is now the team advisor and he does an excellent job.”

Fraser has also stepped down from his formative role as the chairman of Formula Hybrid’s rules committee. “I did that until this past season,” Doug said. “We now have two chairs of the rules committee, one mechanical and one electrical.” Rob Wills, president of Intergrid, a solar power consulting company, is the electrical chair, and Dave Schaller, president of Texas Engineering Systems, is the mechanical chairman.

There’s plenty of competition to be part of Dartmouth’s Formula Hybrid team. “It’s a pretty popular program on campus and it’s not easy to get into,” Fraser commented. “Its makeup is interesting and always changing. Very often, the Dartmouth Formula Hybrid race team is all men and they all live in the same fraternity house. But in other years we’ll have a good number of women and they are from all over campus. You never really know where they’re going to come from.”

Teams work into the night in the paddocks at the 3rd annual Formula Hybrid International Competition.

Every September a fresh group of eager young students are attracted to the Formula Hybrid team. “They show up at the first meetings and arrive in the workshop with their sleeves rolled up ready to do whatever’s thrown at them,” Fraser remarked. “But often, because they’re new, when they ask one of the older team members how they can help they’re told by the experienced people that they’re busy and don’t have the time to explain how to do it. They would rather do it themselves.

“So,” Doug adds, “you’ve got to be pretty determined to earn your way into the team and still be on the team a couple of years later.” Fraser adds that Formula Hybrid teaches the skills of teamwork and interdisciplinary training. “That’s what we’re trying to work on,” he remarked. “Building cross-disciplinary teams is a key element of the competition. It’s about learning to work with people who talk different engineering languages.

“I think it’s been very successful in that way. It really prepares our young engineers to work effectively and successfully in industry. In many ways, that’s the bottom line.”

Next, two weeks down the road, I visit the Thayer School’s Formula Hybrid workshop to meet the team and learn about Dartmouth’s entry in the 2011 Formula Hybrid contest.

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